From patchwork Tue Nov 6 17:30:18 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10670917 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3874A13BF for ; Tue, 6 Nov 2018 17:31:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 223512AB90 for ; Tue, 6 Nov 2018 17:31:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 132BF2ABBE; Tue, 6 Nov 2018 17:31:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE, USER_IN_DEF_DKIM_WL autolearn=unavailable version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D4DAD2AB91 for ; Tue, 6 Nov 2018 17:30:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 68F5F6B0353; Tue, 6 Nov 2018 12:30:50 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 645526B0355; Tue, 6 Nov 2018 12:30:50 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4DED86B0356; Tue, 6 Nov 2018 12:30:50 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by kanga.kvack.org (Postfix) with ESMTP id BAD3B6B0353 for ; Tue, 6 Nov 2018 12:30:49 -0500 (EST) Received: by mail-wm1-f70.google.com with SMTP id a126-v6so10354529wmf.4 for ; Tue, 06 Nov 2018 09:30:49 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=Jrl6Iz5NCriLdz7XOIU1jTj0/A3oQyv/lSX00RAUH3Q=; b=BMRV4+n7mMRyddjGxuwUzT4Q6Byqkvx549VXyD8hp8toX0EU9sBv6lHPzoTitR2kC1 B4cyDb7Ts/6GO0Bi0OYw6Tzo3UMqA4hHoMg+t8TQBVhQm6IwsohfhIxvzKDb1gVDj54V abviPhVvPuGTjAUMmBzxJRQXW4b21t6GtiqdrOqVEigetZJo1zVP9B7BVZhVUBBhMqPJ 5Imtv2emTUppQshe/Qd6rt6eq0vOBQzmfWTaJANkFazQfkXk+wSoNu8pPLi+p85eyY5C Xccbz4kzbRdxrEmlr5xbgmpAEOLpFIRtC5yFWq7+IH/NbSHVirLVpmh1kpZzLQDZ1OhR beAQ== X-Gm-Message-State: AGRZ1gIxZxmfi1COL8RbmFLNf51ByrjoeNXCGGJ/dV81PT0V8fwBXNt2 q9rdOy8Ypgi8xWWECH3OkY758F9hwF67O4Qc5mKw4q2SZ0dzJFf3HqpeU5S83O8Tb6dyNNqoogi rDVw7z/NY2HCN883yvKKdJmRUQWFa2QZYMXUC4PIt4q3CiKvISPtUTLlWmPrFhBp15Xz4pIh6pY xboD8/rNl+qFe4E54JuHzH2Q33F6Pf0giyck3VleBCZqYO1kXmDy2Cs1jfd0cxevmY4i4GAxeGp kEduvQQdo7SY5H5kJvuZRVSDuMQTgHWm6fOjB1XEXZ6GHZ2NQqzHip79lwXjvl0+aJn8/yFPTbM ZB0/QuWYADgBNL6RlJVd1mu8yownG2fL9tIdDI15PaGmiwlF2UbDY5FfzBJMZe+sV98MD/Cbsy4 T X-Received: by 2002:a5d:4a11:: with SMTP id m17-v6mr20132791wrq.259.1541525449184; Tue, 06 Nov 2018 09:30:49 -0800 (PST) X-Received: by 2002:a5d:4a11:: with SMTP id m17-v6mr20132663wrq.259.1541525446897; Tue, 06 Nov 2018 09:30:46 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1541525446; cv=none; d=google.com; s=arc-20160816; b=hQ9yzXrgNRHGcM91vfebG/Mr6N9TH6sUH9b2fVnqKMnN+zzmVN3jmZ/XyEW72eqjI7 nkWqh4JG0Z0CXPiySV+VYe33kzmoKyviH1H5a+50aLJWg37zKEoekh1rPi0JF4B/9MDk m8yovCPp3VgYWJVJfXiWLCqq8WQi1lyO/62YzgkJr+BVhffl+A7priY2rvuwpzIhoaXX umXbqgWFZvAmmKOjKaR1fKalP3QofsHsNaxphDOgftGuZLyK5nTj7D3qjhNaFNjqfvro coqySPk5Zg92K9hEOD4IhAPop39sZc0Cs4K03xWvOKLKsAP9LfhqiAaV6kFw0KKsxmQH IXCA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:dkim-signature; bh=Jrl6Iz5NCriLdz7XOIU1jTj0/A3oQyv/lSX00RAUH3Q=; b=x5q3UzA6ekyuqQiZQms0OYT60+CVTYWc6qid1jUWDuha447VsjzHtHm9iowHALWoiC tHnpXBhHDzdiDs8pgtu3cRjc8YQjS96q2gbuQ+j4POeWoE/U0yAA7OgMG1Co+iUFKjZg OYB6WKlLEbBmTpikJsyzpY6jnz+cDSL66e+L+pH2qufbvunShY0HcNdhOKPJuWD0mogM mhfSQCMwS4JJu3R43hde6aPwmLi4sScvRd9fRhc6wFp3iGGHyMlYJoXBJsLxWzbp4ti/ pFGw3SW+4xl8PuDTmS/h3/T9mU16XazqhEgkG+HKkWQzhuUv69Mwh4KOGL0yo9XF4u5L YVOQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=NWNiXRt1; spf=pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andreyknvl@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id s15-v6sor30460738wrn.35.2018.11.06.09.30.46 for (Google Transport Security); Tue, 06 Nov 2018 09:30:46 -0800 (PST) Received-SPF: pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=NWNiXRt1; spf=pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andreyknvl@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Jrl6Iz5NCriLdz7XOIU1jTj0/A3oQyv/lSX00RAUH3Q=; b=NWNiXRt1Ux5THpX0L7pcX/ZViA2r5zT6Kxy5RWhRIC9u16ixfY5JQJ6YhG8xZDVbpH roiu8neyB2Gjp1NPtSzfJh+k9LE8Tjqc3pMcowKAEpaztNrw2f8OD07oxq8r+kK5p5H4 RID8L+R2lSNxLDCNlbemLCJLmNbbnwIQvqC+Ws90EtjfzN40tF96IpTYv2YoglztRP0J mqdQGjt0q2fvWCw786KxomhUDrK8cr/W4rUHBlqAh7mSb1ufYUv+ewwocaPC7wT8r4yb JI5GhhOmdWFnozPE1sYnrbZejwo6e1DdjyrmlbdZaxXOffy1Z5LEoedIk6r/Vh/NpE97 wkPg== X-Google-Smtp-Source: AJdET5fp9v51PqZ2CzbwGPv8lnMr9AENQJH8+pX0neAYJxsUkwdQkH4stqPZGiON7CnvcnlsQ8JzyA== X-Received: by 2002:a5d:4cc6:: with SMTP id c6-v6mr2013340wrt.75.1541525445797; Tue, 06 Nov 2018 09:30:45 -0800 (PST) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:84be:a42a:826d:c530]) by smtp.gmail.com with ESMTPSA id z17-v6sm16328416wrm.65.2018.11.06.09.30.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Nov 2018 09:30:44 -0800 (PST) From: Andrey Konovalov To: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Catalin Marinas , Will Deacon , Christoph Lameter , Andrew Morton , Mark Rutland , Nick Desaulniers , Marc Zyngier , Dave Martin , Ard Biesheuvel , "Eric W . Biederman" , Ingo Molnar , Paul Lawrence , Geert Uytterhoeven , Arnd Bergmann , "Kirill A . Shutemov" , Greg Kroah-Hartman , Kate Stewart , Mike Rapoport , kasan-dev@googlegroups.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sparse@vger.kernel.org, linux-mm@kvack.org, linux-kbuild@vger.kernel.org Cc: Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Jann Horn , Mark Brand , Chintan Pandya , Vishwath Mohan , Andrey Konovalov Subject: [PATCH v10 03/22] kasan: move common generic and tag-based code to common.c Date: Tue, 6 Nov 2018 18:30:18 +0100 Message-Id: X-Mailer: git-send-email 2.19.1.930.g4563a0d9d0-goog In-Reply-To: References: MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Tag-based KASAN reuses a significant part of the generic KASAN code, so move the common parts to common.c without any functional changes. Reviewed-by: Andrey Ryabinin Reviewed-by: Dmitry Vyukov Signed-off-by: Andrey Konovalov --- mm/kasan/Makefile | 5 +- mm/kasan/common.c | 603 ++++++++++++++++++++++++++++++++++++++++++++++ mm/kasan/kasan.c | 570 +------------------------------------------ mm/kasan/kasan.h | 5 + 4 files changed, 614 insertions(+), 569 deletions(-) create mode 100644 mm/kasan/common.c diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile index 3289db38bc87..a6df14bffb6b 100644 --- a/mm/kasan/Makefile +++ b/mm/kasan/Makefile @@ -1,11 +1,14 @@ # SPDX-License-Identifier: GPL-2.0 KASAN_SANITIZE := n +UBSAN_SANITIZE_common.o := n UBSAN_SANITIZE_kasan.o := n KCOV_INSTRUMENT := n CFLAGS_REMOVE_kasan.o = -pg # Function splitter causes unnecessary splits in __asan_load1/__asan_store1 # see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63533 + +CFLAGS_common.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) CFLAGS_kasan.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -obj-y := kasan.o report.o kasan_init.o quarantine.o +obj-y := common.o kasan.o report.o kasan_init.o quarantine.o diff --git a/mm/kasan/common.c b/mm/kasan/common.c new file mode 100644 index 000000000000..5f68c93734ba --- /dev/null +++ b/mm/kasan/common.c @@ -0,0 +1,603 @@ +/* + * This file contains common generic and tag-based KASAN code. + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * Author: Andrey Ryabinin + * + * Some code borrowed from https://github.com/xairy/kasan-prototype by + * Andrey Konovalov + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "kasan.h" +#include "../slab.h" + +static inline int in_irqentry_text(unsigned long ptr) +{ + return (ptr >= (unsigned long)&__irqentry_text_start && + ptr < (unsigned long)&__irqentry_text_end) || + (ptr >= (unsigned long)&__softirqentry_text_start && + ptr < (unsigned long)&__softirqentry_text_end); +} + +static inline void filter_irq_stacks(struct stack_trace *trace) +{ + int i; + + if (!trace->nr_entries) + return; + for (i = 0; i < trace->nr_entries; i++) + if (in_irqentry_text(trace->entries[i])) { + /* Include the irqentry function into the stack. */ + trace->nr_entries = i + 1; + break; + } +} + +static inline depot_stack_handle_t save_stack(gfp_t flags) +{ + unsigned long entries[KASAN_STACK_DEPTH]; + struct stack_trace trace = { + .nr_entries = 0, + .entries = entries, + .max_entries = KASAN_STACK_DEPTH, + .skip = 0 + }; + + save_stack_trace(&trace); + filter_irq_stacks(&trace); + if (trace.nr_entries != 0 && + trace.entries[trace.nr_entries-1] == ULONG_MAX) + trace.nr_entries--; + + return depot_save_stack(&trace, flags); +} + +static inline void set_track(struct kasan_track *track, gfp_t flags) +{ + track->pid = current->pid; + track->stack = save_stack(flags); +} + +void kasan_enable_current(void) +{ + current->kasan_depth++; +} + +void kasan_disable_current(void) +{ + current->kasan_depth--; +} + +void kasan_check_read(const volatile void *p, unsigned int size) +{ + check_memory_region((unsigned long)p, size, false, _RET_IP_); +} +EXPORT_SYMBOL(kasan_check_read); + +void kasan_check_write(const volatile void *p, unsigned int size) +{ + check_memory_region((unsigned long)p, size, true, _RET_IP_); +} +EXPORT_SYMBOL(kasan_check_write); + +#undef memset +void *memset(void *addr, int c, size_t len) +{ + check_memory_region((unsigned long)addr, len, true, _RET_IP_); + + return __memset(addr, c, len); +} + +#undef memmove +void *memmove(void *dest, const void *src, size_t len) +{ + check_memory_region((unsigned long)src, len, false, _RET_IP_); + check_memory_region((unsigned long)dest, len, true, _RET_IP_); + + return __memmove(dest, src, len); +} + +#undef memcpy +void *memcpy(void *dest, const void *src, size_t len) +{ + check_memory_region((unsigned long)src, len, false, _RET_IP_); + check_memory_region((unsigned long)dest, len, true, _RET_IP_); + + return __memcpy(dest, src, len); +} + +/* + * Poisons the shadow memory for 'size' bytes starting from 'addr'. + * Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE. + */ +void kasan_poison_shadow(const void *address, size_t size, u8 value) +{ + void *shadow_start, *shadow_end; + + shadow_start = kasan_mem_to_shadow(address); + shadow_end = kasan_mem_to_shadow(address + size); + + __memset(shadow_start, value, shadow_end - shadow_start); +} + +void kasan_unpoison_shadow(const void *address, size_t size) +{ + kasan_poison_shadow(address, size, 0); + + if (size & KASAN_SHADOW_MASK) { + u8 *shadow = (u8 *)kasan_mem_to_shadow(address + size); + *shadow = size & KASAN_SHADOW_MASK; + } +} + +static void __kasan_unpoison_stack(struct task_struct *task, const void *sp) +{ + void *base = task_stack_page(task); + size_t size = sp - base; + + kasan_unpoison_shadow(base, size); +} + +/* Unpoison the entire stack for a task. */ +void kasan_unpoison_task_stack(struct task_struct *task) +{ + __kasan_unpoison_stack(task, task_stack_page(task) + THREAD_SIZE); +} + +/* Unpoison the stack for the current task beyond a watermark sp value. */ +asmlinkage void kasan_unpoison_task_stack_below(const void *watermark) +{ + /* + * Calculate the task stack base address. Avoid using 'current' + * because this function is called by early resume code which hasn't + * yet set up the percpu register (%gs). + */ + void *base = (void *)((unsigned long)watermark & ~(THREAD_SIZE - 1)); + + kasan_unpoison_shadow(base, watermark - base); +} + +/* + * Clear all poison for the region between the current SP and a provided + * watermark value, as is sometimes required prior to hand-crafted asm function + * returns in the middle of functions. + */ +void kasan_unpoison_stack_above_sp_to(const void *watermark) +{ + const void *sp = __builtin_frame_address(0); + size_t size = watermark - sp; + + if (WARN_ON(sp > watermark)) + return; + kasan_unpoison_shadow(sp, size); +} + +void kasan_alloc_pages(struct page *page, unsigned int order) +{ + if (likely(!PageHighMem(page))) + kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order); +} + +void kasan_free_pages(struct page *page, unsigned int order) +{ + if (likely(!PageHighMem(page))) + kasan_poison_shadow(page_address(page), + PAGE_SIZE << order, + KASAN_FREE_PAGE); +} + +/* + * Adaptive redzone policy taken from the userspace AddressSanitizer runtime. + * For larger allocations larger redzones are used. + */ +static inline unsigned int optimal_redzone(unsigned int object_size) +{ + return + object_size <= 64 - 16 ? 16 : + object_size <= 128 - 32 ? 32 : + object_size <= 512 - 64 ? 64 : + object_size <= 4096 - 128 ? 128 : + object_size <= (1 << 14) - 256 ? 256 : + object_size <= (1 << 15) - 512 ? 512 : + object_size <= (1 << 16) - 1024 ? 1024 : 2048; +} + +void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, + slab_flags_t *flags) +{ + unsigned int orig_size = *size; + int redzone_adjust; + + /* Add alloc meta. */ + cache->kasan_info.alloc_meta_offset = *size; + *size += sizeof(struct kasan_alloc_meta); + + /* Add free meta. */ + if (cache->flags & SLAB_TYPESAFE_BY_RCU || cache->ctor || + cache->object_size < sizeof(struct kasan_free_meta)) { + cache->kasan_info.free_meta_offset = *size; + *size += sizeof(struct kasan_free_meta); + } + redzone_adjust = optimal_redzone(cache->object_size) - + (*size - cache->object_size); + + if (redzone_adjust > 0) + *size += redzone_adjust; + + *size = min_t(unsigned int, KMALLOC_MAX_SIZE, + max(*size, cache->object_size + + optimal_redzone(cache->object_size))); + + /* + * If the metadata doesn't fit, don't enable KASAN at all. + */ + if (*size <= cache->kasan_info.alloc_meta_offset || + *size <= cache->kasan_info.free_meta_offset) { + cache->kasan_info.alloc_meta_offset = 0; + cache->kasan_info.free_meta_offset = 0; + *size = orig_size; + return; + } + + *flags |= SLAB_KASAN; +} + +size_t kasan_metadata_size(struct kmem_cache *cache) +{ + return (cache->kasan_info.alloc_meta_offset ? + sizeof(struct kasan_alloc_meta) : 0) + + (cache->kasan_info.free_meta_offset ? + sizeof(struct kasan_free_meta) : 0); +} + +struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache, + const void *object) +{ + BUILD_BUG_ON(sizeof(struct kasan_alloc_meta) > 32); + return (void *)object + cache->kasan_info.alloc_meta_offset; +} + +struct kasan_free_meta *get_free_info(struct kmem_cache *cache, + const void *object) +{ + BUILD_BUG_ON(sizeof(struct kasan_free_meta) > 32); + return (void *)object + cache->kasan_info.free_meta_offset; +} + +void kasan_poison_slab(struct page *page) +{ + kasan_poison_shadow(page_address(page), + PAGE_SIZE << compound_order(page), + KASAN_KMALLOC_REDZONE); +} + +void kasan_unpoison_object_data(struct kmem_cache *cache, void *object) +{ + kasan_unpoison_shadow(object, cache->object_size); +} + +void kasan_poison_object_data(struct kmem_cache *cache, void *object) +{ + kasan_poison_shadow(object, + round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE), + KASAN_KMALLOC_REDZONE); +} + +void *kasan_init_slab_obj(struct kmem_cache *cache, const void *object) +{ + struct kasan_alloc_meta *alloc_info; + + if (!(cache->flags & SLAB_KASAN)) + return (void *)object; + + alloc_info = get_alloc_info(cache, object); + __memset(alloc_info, 0, sizeof(*alloc_info)); + + return (void *)object; +} + +void *kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags) +{ + return kasan_kmalloc(cache, object, cache->object_size, flags); +} + +static bool __kasan_slab_free(struct kmem_cache *cache, void *object, + unsigned long ip, bool quarantine) +{ + s8 shadow_byte; + unsigned long rounded_up_size; + + if (unlikely(nearest_obj(cache, virt_to_head_page(object), object) != + object)) { + kasan_report_invalid_free(object, ip); + return true; + } + + /* RCU slabs could be legally used after free within the RCU period */ + if (unlikely(cache->flags & SLAB_TYPESAFE_BY_RCU)) + return false; + + shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object)); + if (shadow_byte < 0 || shadow_byte >= KASAN_SHADOW_SCALE_SIZE) { + kasan_report_invalid_free(object, ip); + return true; + } + + rounded_up_size = round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE); + kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE); + + if (!quarantine || unlikely(!(cache->flags & SLAB_KASAN))) + return false; + + set_track(&get_alloc_info(cache, object)->free_track, GFP_NOWAIT); + quarantine_put(get_free_info(cache, object), cache); + return true; +} + +bool kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip) +{ + return __kasan_slab_free(cache, object, ip, true); +} + +void *kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size, + gfp_t flags) +{ + unsigned long redzone_start; + unsigned long redzone_end; + + if (gfpflags_allow_blocking(flags)) + quarantine_reduce(); + + if (unlikely(object == NULL)) + return NULL; + + redzone_start = round_up((unsigned long)(object + size), + KASAN_SHADOW_SCALE_SIZE); + redzone_end = round_up((unsigned long)object + cache->object_size, + KASAN_SHADOW_SCALE_SIZE); + + kasan_unpoison_shadow(object, size); + kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, + KASAN_KMALLOC_REDZONE); + + if (cache->flags & SLAB_KASAN) + set_track(&get_alloc_info(cache, object)->alloc_track, flags); + + return (void *)object; +} +EXPORT_SYMBOL(kasan_kmalloc); + +void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags) +{ + struct page *page; + unsigned long redzone_start; + unsigned long redzone_end; + + if (gfpflags_allow_blocking(flags)) + quarantine_reduce(); + + if (unlikely(ptr == NULL)) + return NULL; + + page = virt_to_page(ptr); + redzone_start = round_up((unsigned long)(ptr + size), + KASAN_SHADOW_SCALE_SIZE); + redzone_end = (unsigned long)ptr + (PAGE_SIZE << compound_order(page)); + + kasan_unpoison_shadow(ptr, size); + kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, + KASAN_PAGE_REDZONE); + + return (void *)ptr; +} + +void *kasan_krealloc(const void *object, size_t size, gfp_t flags) +{ + struct page *page; + + if (unlikely(object == ZERO_SIZE_PTR)) + return (void *)object; + + page = virt_to_head_page(object); + + if (unlikely(!PageSlab(page))) + return kasan_kmalloc_large(object, size, flags); + else + return kasan_kmalloc(page->slab_cache, object, size, flags); +} + +void kasan_poison_kfree(void *ptr, unsigned long ip) +{ + struct page *page; + + page = virt_to_head_page(ptr); + + if (unlikely(!PageSlab(page))) { + if (ptr != page_address(page)) { + kasan_report_invalid_free(ptr, ip); + return; + } + kasan_poison_shadow(ptr, PAGE_SIZE << compound_order(page), + KASAN_FREE_PAGE); + } else { + __kasan_slab_free(page->slab_cache, ptr, ip, false); + } +} + +void kasan_kfree_large(void *ptr, unsigned long ip) +{ + if (ptr != page_address(virt_to_head_page(ptr))) + kasan_report_invalid_free(ptr, ip); + /* The object will be poisoned by page_alloc. */ +} + +int kasan_module_alloc(void *addr, size_t size) +{ + void *ret; + size_t scaled_size; + size_t shadow_size; + unsigned long shadow_start; + + shadow_start = (unsigned long)kasan_mem_to_shadow(addr); + scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT; + shadow_size = round_up(scaled_size, PAGE_SIZE); + + if (WARN_ON(!PAGE_ALIGNED(shadow_start))) + return -EINVAL; + + ret = __vmalloc_node_range(shadow_size, 1, shadow_start, + shadow_start + shadow_size, + GFP_KERNEL | __GFP_ZERO, + PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE, + __builtin_return_address(0)); + + if (ret) { + find_vm_area(addr)->flags |= VM_KASAN; + kmemleak_ignore(ret); + return 0; + } + + return -ENOMEM; +} + +void kasan_free_shadow(const struct vm_struct *vm) +{ + if (vm->flags & VM_KASAN) + vfree(kasan_mem_to_shadow(vm->addr)); +} + +#ifdef CONFIG_MEMORY_HOTPLUG +static bool shadow_mapped(unsigned long addr) +{ + pgd_t *pgd = pgd_offset_k(addr); + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + + if (pgd_none(*pgd)) + return false; + p4d = p4d_offset(pgd, addr); + if (p4d_none(*p4d)) + return false; + pud = pud_offset(p4d, addr); + if (pud_none(*pud)) + return false; + + /* + * We can't use pud_large() or pud_huge(), the first one is + * arch-specific, the last one depends on HUGETLB_PAGE. So let's abuse + * pud_bad(), if pud is bad then it's bad because it's huge. + */ + if (pud_bad(*pud)) + return true; + pmd = pmd_offset(pud, addr); + if (pmd_none(*pmd)) + return false; + + if (pmd_bad(*pmd)) + return true; + pte = pte_offset_kernel(pmd, addr); + return !pte_none(*pte); +} + +static int __meminit kasan_mem_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct memory_notify *mem_data = data; + unsigned long nr_shadow_pages, start_kaddr, shadow_start; + unsigned long shadow_end, shadow_size; + + nr_shadow_pages = mem_data->nr_pages >> KASAN_SHADOW_SCALE_SHIFT; + start_kaddr = (unsigned long)pfn_to_kaddr(mem_data->start_pfn); + shadow_start = (unsigned long)kasan_mem_to_shadow((void *)start_kaddr); + shadow_size = nr_shadow_pages << PAGE_SHIFT; + shadow_end = shadow_start + shadow_size; + + if (WARN_ON(mem_data->nr_pages % KASAN_SHADOW_SCALE_SIZE) || + WARN_ON(start_kaddr % (KASAN_SHADOW_SCALE_SIZE << PAGE_SHIFT))) + return NOTIFY_BAD; + + switch (action) { + case MEM_GOING_ONLINE: { + void *ret; + + /* + * If shadow is mapped already than it must have been mapped + * during the boot. This could happen if we onlining previously + * offlined memory. + */ + if (shadow_mapped(shadow_start)) + return NOTIFY_OK; + + ret = __vmalloc_node_range(shadow_size, PAGE_SIZE, shadow_start, + shadow_end, GFP_KERNEL, + PAGE_KERNEL, VM_NO_GUARD, + pfn_to_nid(mem_data->start_pfn), + __builtin_return_address(0)); + if (!ret) + return NOTIFY_BAD; + + kmemleak_ignore(ret); + return NOTIFY_OK; + } + case MEM_CANCEL_ONLINE: + case MEM_OFFLINE: { + struct vm_struct *vm; + + /* + * shadow_start was either mapped during boot by kasan_init() + * or during memory online by __vmalloc_node_range(). + * In the latter case we can use vfree() to free shadow. + * Non-NULL result of the find_vm_area() will tell us if + * that was the second case. + * + * Currently it's not possible to free shadow mapped + * during boot by kasan_init(). It's because the code + * to do that hasn't been written yet. So we'll just + * leak the memory. + */ + vm = find_vm_area((void *)shadow_start); + if (vm) + vfree((void *)shadow_start); + } + } + + return NOTIFY_OK; +} + +static int __init kasan_memhotplug_init(void) +{ + hotplug_memory_notifier(kasan_mem_notifier, 0); + + return 0; +} + +core_initcall(kasan_memhotplug_init); +#endif diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index 55deff17a4d9..44ec228de0a2 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -1,5 +1,5 @@ /* - * This file contains shadow memory manipulation code. + * This file contains core KASAN code. * * Copyright (c) 2014 Samsung Electronics Co., Ltd. * Author: Andrey Ryabinin @@ -40,82 +40,6 @@ #include "kasan.h" #include "../slab.h" -void kasan_enable_current(void) -{ - current->kasan_depth++; -} - -void kasan_disable_current(void) -{ - current->kasan_depth--; -} - -/* - * Poisons the shadow memory for 'size' bytes starting from 'addr'. - * Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE. - */ -static void kasan_poison_shadow(const void *address, size_t size, u8 value) -{ - void *shadow_start, *shadow_end; - - shadow_start = kasan_mem_to_shadow(address); - shadow_end = kasan_mem_to_shadow(address + size); - - memset(shadow_start, value, shadow_end - shadow_start); -} - -void kasan_unpoison_shadow(const void *address, size_t size) -{ - kasan_poison_shadow(address, size, 0); - - if (size & KASAN_SHADOW_MASK) { - u8 *shadow = (u8 *)kasan_mem_to_shadow(address + size); - *shadow = size & KASAN_SHADOW_MASK; - } -} - -static void __kasan_unpoison_stack(struct task_struct *task, const void *sp) -{ - void *base = task_stack_page(task); - size_t size = sp - base; - - kasan_unpoison_shadow(base, size); -} - -/* Unpoison the entire stack for a task. */ -void kasan_unpoison_task_stack(struct task_struct *task) -{ - __kasan_unpoison_stack(task, task_stack_page(task) + THREAD_SIZE); -} - -/* Unpoison the stack for the current task beyond a watermark sp value. */ -asmlinkage void kasan_unpoison_task_stack_below(const void *watermark) -{ - /* - * Calculate the task stack base address. Avoid using 'current' - * because this function is called by early resume code which hasn't - * yet set up the percpu register (%gs). - */ - void *base = (void *)((unsigned long)watermark & ~(THREAD_SIZE - 1)); - - kasan_unpoison_shadow(base, watermark - base); -} - -/* - * Clear all poison for the region between the current SP and a provided - * watermark value, as is sometimes required prior to hand-crafted asm function - * returns in the middle of functions. - */ -void kasan_unpoison_stack_above_sp_to(const void *watermark) -{ - const void *sp = __builtin_frame_address(0); - size_t size = watermark - sp; - - if (WARN_ON(sp > watermark)) - return; - kasan_unpoison_shadow(sp, size); -} - /* * All functions below always inlined so compiler could * perform better optimizations in each of __asan_loadX/__assn_storeX @@ -260,121 +184,12 @@ static __always_inline void check_memory_region_inline(unsigned long addr, kasan_report(addr, size, write, ret_ip); } -static void check_memory_region(unsigned long addr, - size_t size, bool write, +void check_memory_region(unsigned long addr, size_t size, bool write, unsigned long ret_ip) { check_memory_region_inline(addr, size, write, ret_ip); } -void kasan_check_read(const volatile void *p, unsigned int size) -{ - check_memory_region((unsigned long)p, size, false, _RET_IP_); -} -EXPORT_SYMBOL(kasan_check_read); - -void kasan_check_write(const volatile void *p, unsigned int size) -{ - check_memory_region((unsigned long)p, size, true, _RET_IP_); -} -EXPORT_SYMBOL(kasan_check_write); - -#undef memset -void *memset(void *addr, int c, size_t len) -{ - check_memory_region((unsigned long)addr, len, true, _RET_IP_); - - return __memset(addr, c, len); -} - -#undef memmove -void *memmove(void *dest, const void *src, size_t len) -{ - check_memory_region((unsigned long)src, len, false, _RET_IP_); - check_memory_region((unsigned long)dest, len, true, _RET_IP_); - - return __memmove(dest, src, len); -} - -#undef memcpy -void *memcpy(void *dest, const void *src, size_t len) -{ - check_memory_region((unsigned long)src, len, false, _RET_IP_); - check_memory_region((unsigned long)dest, len, true, _RET_IP_); - - return __memcpy(dest, src, len); -} - -void kasan_alloc_pages(struct page *page, unsigned int order) -{ - if (likely(!PageHighMem(page))) - kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order); -} - -void kasan_free_pages(struct page *page, unsigned int order) -{ - if (likely(!PageHighMem(page))) - kasan_poison_shadow(page_address(page), - PAGE_SIZE << order, - KASAN_FREE_PAGE); -} - -/* - * Adaptive redzone policy taken from the userspace AddressSanitizer runtime. - * For larger allocations larger redzones are used. - */ -static unsigned int optimal_redzone(unsigned int object_size) -{ - return - object_size <= 64 - 16 ? 16 : - object_size <= 128 - 32 ? 32 : - object_size <= 512 - 64 ? 64 : - object_size <= 4096 - 128 ? 128 : - object_size <= (1 << 14) - 256 ? 256 : - object_size <= (1 << 15) - 512 ? 512 : - object_size <= (1 << 16) - 1024 ? 1024 : 2048; -} - -void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, - slab_flags_t *flags) -{ - unsigned int orig_size = *size; - int redzone_adjust; - - /* Add alloc meta. */ - cache->kasan_info.alloc_meta_offset = *size; - *size += sizeof(struct kasan_alloc_meta); - - /* Add free meta. */ - if (cache->flags & SLAB_TYPESAFE_BY_RCU || cache->ctor || - cache->object_size < sizeof(struct kasan_free_meta)) { - cache->kasan_info.free_meta_offset = *size; - *size += sizeof(struct kasan_free_meta); - } - redzone_adjust = optimal_redzone(cache->object_size) - - (*size - cache->object_size); - - if (redzone_adjust > 0) - *size += redzone_adjust; - - *size = min_t(unsigned int, KMALLOC_MAX_SIZE, - max(*size, cache->object_size + - optimal_redzone(cache->object_size))); - - /* - * If the metadata doesn't fit, don't enable KASAN at all. - */ - if (*size <= cache->kasan_info.alloc_meta_offset || - *size <= cache->kasan_info.free_meta_offset) { - cache->kasan_info.alloc_meta_offset = 0; - cache->kasan_info.free_meta_offset = 0; - *size = orig_size; - return; - } - - *flags |= SLAB_KASAN; -} - void kasan_cache_shrink(struct kmem_cache *cache) { quarantine_remove_cache(cache); @@ -386,277 +201,6 @@ void kasan_cache_shutdown(struct kmem_cache *cache) quarantine_remove_cache(cache); } -size_t kasan_metadata_size(struct kmem_cache *cache) -{ - return (cache->kasan_info.alloc_meta_offset ? - sizeof(struct kasan_alloc_meta) : 0) + - (cache->kasan_info.free_meta_offset ? - sizeof(struct kasan_free_meta) : 0); -} - -void kasan_poison_slab(struct page *page) -{ - kasan_poison_shadow(page_address(page), - PAGE_SIZE << compound_order(page), - KASAN_KMALLOC_REDZONE); -} - -void kasan_unpoison_object_data(struct kmem_cache *cache, void *object) -{ - kasan_unpoison_shadow(object, cache->object_size); -} - -void kasan_poison_object_data(struct kmem_cache *cache, void *object) -{ - kasan_poison_shadow(object, - round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE), - KASAN_KMALLOC_REDZONE); -} - -static inline int in_irqentry_text(unsigned long ptr) -{ - return (ptr >= (unsigned long)&__irqentry_text_start && - ptr < (unsigned long)&__irqentry_text_end) || - (ptr >= (unsigned long)&__softirqentry_text_start && - ptr < (unsigned long)&__softirqentry_text_end); -} - -static inline void filter_irq_stacks(struct stack_trace *trace) -{ - int i; - - if (!trace->nr_entries) - return; - for (i = 0; i < trace->nr_entries; i++) - if (in_irqentry_text(trace->entries[i])) { - /* Include the irqentry function into the stack. */ - trace->nr_entries = i + 1; - break; - } -} - -static inline depot_stack_handle_t save_stack(gfp_t flags) -{ - unsigned long entries[KASAN_STACK_DEPTH]; - struct stack_trace trace = { - .nr_entries = 0, - .entries = entries, - .max_entries = KASAN_STACK_DEPTH, - .skip = 0 - }; - - save_stack_trace(&trace); - filter_irq_stacks(&trace); - if (trace.nr_entries != 0 && - trace.entries[trace.nr_entries-1] == ULONG_MAX) - trace.nr_entries--; - - return depot_save_stack(&trace, flags); -} - -static inline void set_track(struct kasan_track *track, gfp_t flags) -{ - track->pid = current->pid; - track->stack = save_stack(flags); -} - -struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache, - const void *object) -{ - BUILD_BUG_ON(sizeof(struct kasan_alloc_meta) > 32); - return (void *)object + cache->kasan_info.alloc_meta_offset; -} - -struct kasan_free_meta *get_free_info(struct kmem_cache *cache, - const void *object) -{ - BUILD_BUG_ON(sizeof(struct kasan_free_meta) > 32); - return (void *)object + cache->kasan_info.free_meta_offset; -} - -void *kasan_init_slab_obj(struct kmem_cache *cache, const void *object) -{ - struct kasan_alloc_meta *alloc_info; - - if (!(cache->flags & SLAB_KASAN)) - return (void *)object; - - alloc_info = get_alloc_info(cache, object); - __memset(alloc_info, 0, sizeof(*alloc_info)); - - return (void *)object; -} - -void *kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags) -{ - return kasan_kmalloc(cache, object, cache->object_size, flags); -} - -static bool __kasan_slab_free(struct kmem_cache *cache, void *object, - unsigned long ip, bool quarantine) -{ - s8 shadow_byte; - unsigned long rounded_up_size; - - if (unlikely(nearest_obj(cache, virt_to_head_page(object), object) != - object)) { - kasan_report_invalid_free(object, ip); - return true; - } - - /* RCU slabs could be legally used after free within the RCU period */ - if (unlikely(cache->flags & SLAB_TYPESAFE_BY_RCU)) - return false; - - shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object)); - if (shadow_byte < 0 || shadow_byte >= KASAN_SHADOW_SCALE_SIZE) { - kasan_report_invalid_free(object, ip); - return true; - } - - rounded_up_size = round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE); - kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE); - - if (!quarantine || unlikely(!(cache->flags & SLAB_KASAN))) - return false; - - set_track(&get_alloc_info(cache, object)->free_track, GFP_NOWAIT); - quarantine_put(get_free_info(cache, object), cache); - return true; -} - -bool kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip) -{ - return __kasan_slab_free(cache, object, ip, true); -} - -void *kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size, - gfp_t flags) -{ - unsigned long redzone_start; - unsigned long redzone_end; - - if (gfpflags_allow_blocking(flags)) - quarantine_reduce(); - - if (unlikely(object == NULL)) - return NULL; - - redzone_start = round_up((unsigned long)(object + size), - KASAN_SHADOW_SCALE_SIZE); - redzone_end = round_up((unsigned long)object + cache->object_size, - KASAN_SHADOW_SCALE_SIZE); - - kasan_unpoison_shadow(object, size); - kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, - KASAN_KMALLOC_REDZONE); - - if (cache->flags & SLAB_KASAN) - set_track(&get_alloc_info(cache, object)->alloc_track, flags); - - return (void *)object; -} -EXPORT_SYMBOL(kasan_kmalloc); - -void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags) -{ - struct page *page; - unsigned long redzone_start; - unsigned long redzone_end; - - if (gfpflags_allow_blocking(flags)) - quarantine_reduce(); - - if (unlikely(ptr == NULL)) - return NULL; - - page = virt_to_page(ptr); - redzone_start = round_up((unsigned long)(ptr + size), - KASAN_SHADOW_SCALE_SIZE); - redzone_end = (unsigned long)ptr + (PAGE_SIZE << compound_order(page)); - - kasan_unpoison_shadow(ptr, size); - kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start, - KASAN_PAGE_REDZONE); - - return (void *)ptr; -} - -void *kasan_krealloc(const void *object, size_t size, gfp_t flags) -{ - struct page *page; - - if (unlikely(object == ZERO_SIZE_PTR)) - return ZERO_SIZE_PTR; - - page = virt_to_head_page(object); - - if (unlikely(!PageSlab(page))) - return kasan_kmalloc_large(object, size, flags); - else - return kasan_kmalloc(page->slab_cache, object, size, flags); -} - -void kasan_poison_kfree(void *ptr, unsigned long ip) -{ - struct page *page; - - page = virt_to_head_page(ptr); - - if (unlikely(!PageSlab(page))) { - if (ptr != page_address(page)) { - kasan_report_invalid_free(ptr, ip); - return; - } - kasan_poison_shadow(ptr, PAGE_SIZE << compound_order(page), - KASAN_FREE_PAGE); - } else { - __kasan_slab_free(page->slab_cache, ptr, ip, false); - } -} - -void kasan_kfree_large(void *ptr, unsigned long ip) -{ - if (ptr != page_address(virt_to_head_page(ptr))) - kasan_report_invalid_free(ptr, ip); - /* The object will be poisoned by page_alloc. */ -} - -int kasan_module_alloc(void *addr, size_t size) -{ - void *ret; - size_t scaled_size; - size_t shadow_size; - unsigned long shadow_start; - - shadow_start = (unsigned long)kasan_mem_to_shadow(addr); - scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT; - shadow_size = round_up(scaled_size, PAGE_SIZE); - - if (WARN_ON(!PAGE_ALIGNED(shadow_start))) - return -EINVAL; - - ret = __vmalloc_node_range(shadow_size, 1, shadow_start, - shadow_start + shadow_size, - GFP_KERNEL | __GFP_ZERO, - PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE, - __builtin_return_address(0)); - - if (ret) { - find_vm_area(addr)->flags |= VM_KASAN; - kmemleak_ignore(ret); - return 0; - } - - return -ENOMEM; -} - -void kasan_free_shadow(const struct vm_struct *vm) -{ - if (vm->flags & VM_KASAN) - vfree(kasan_mem_to_shadow(vm->addr)); -} - static void register_global(struct kasan_global *global) { size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE); @@ -797,113 +341,3 @@ DEFINE_ASAN_SET_SHADOW(f2); DEFINE_ASAN_SET_SHADOW(f3); DEFINE_ASAN_SET_SHADOW(f5); DEFINE_ASAN_SET_SHADOW(f8); - -#ifdef CONFIG_MEMORY_HOTPLUG -static bool shadow_mapped(unsigned long addr) -{ - pgd_t *pgd = pgd_offset_k(addr); - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - if (pgd_none(*pgd)) - return false; - p4d = p4d_offset(pgd, addr); - if (p4d_none(*p4d)) - return false; - pud = pud_offset(p4d, addr); - if (pud_none(*pud)) - return false; - - /* - * We can't use pud_large() or pud_huge(), the first one is - * arch-specific, the last one depends on HUGETLB_PAGE. So let's abuse - * pud_bad(), if pud is bad then it's bad because it's huge. - */ - if (pud_bad(*pud)) - return true; - pmd = pmd_offset(pud, addr); - if (pmd_none(*pmd)) - return false; - - if (pmd_bad(*pmd)) - return true; - pte = pte_offset_kernel(pmd, addr); - return !pte_none(*pte); -} - -static int __meminit kasan_mem_notifier(struct notifier_block *nb, - unsigned long action, void *data) -{ - struct memory_notify *mem_data = data; - unsigned long nr_shadow_pages, start_kaddr, shadow_start; - unsigned long shadow_end, shadow_size; - - nr_shadow_pages = mem_data->nr_pages >> KASAN_SHADOW_SCALE_SHIFT; - start_kaddr = (unsigned long)pfn_to_kaddr(mem_data->start_pfn); - shadow_start = (unsigned long)kasan_mem_to_shadow((void *)start_kaddr); - shadow_size = nr_shadow_pages << PAGE_SHIFT; - shadow_end = shadow_start + shadow_size; - - if (WARN_ON(mem_data->nr_pages % KASAN_SHADOW_SCALE_SIZE) || - WARN_ON(start_kaddr % (KASAN_SHADOW_SCALE_SIZE << PAGE_SHIFT))) - return NOTIFY_BAD; - - switch (action) { - case MEM_GOING_ONLINE: { - void *ret; - - /* - * If shadow is mapped already than it must have been mapped - * during the boot. This could happen if we onlining previously - * offlined memory. - */ - if (shadow_mapped(shadow_start)) - return NOTIFY_OK; - - ret = __vmalloc_node_range(shadow_size, PAGE_SIZE, shadow_start, - shadow_end, GFP_KERNEL, - PAGE_KERNEL, VM_NO_GUARD, - pfn_to_nid(mem_data->start_pfn), - __builtin_return_address(0)); - if (!ret) - return NOTIFY_BAD; - - kmemleak_ignore(ret); - return NOTIFY_OK; - } - case MEM_CANCEL_ONLINE: - case MEM_OFFLINE: { - struct vm_struct *vm; - - /* - * shadow_start was either mapped during boot by kasan_init() - * or during memory online by __vmalloc_node_range(). - * In the latter case we can use vfree() to free shadow. - * Non-NULL result of the find_vm_area() will tell us if - * that was the second case. - * - * Currently it's not possible to free shadow mapped - * during boot by kasan_init(). It's because the code - * to do that hasn't been written yet. So we'll just - * leak the memory. - */ - vm = find_vm_area((void *)shadow_start); - if (vm) - vfree((void *)shadow_start); - } - } - - return NOTIFY_OK; -} - -static int __init kasan_memhotplug_init(void) -{ - hotplug_memory_notifier(kasan_mem_notifier, 0); - - return 0; -} - -core_initcall(kasan_memhotplug_init); -#endif diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index c12dcfde2ebd..659463800f10 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -105,6 +105,11 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr) << KASAN_SHADOW_SCALE_SHIFT); } +void kasan_poison_shadow(const void *address, size_t size, u8 value); + +void check_memory_region(unsigned long addr, size_t size, bool write, + unsigned long ret_ip); + void kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip); void kasan_report_invalid_free(void *object, unsigned long ip);